There are 4 main types of safe locking mechanisms used in modern safes. This article will briefly introduce and summarize each of the 4 types: key locks, mechanical combination locks, electronic locks, and time locks.
Key locks are the standard locks used in doors, vehicles, padlocks, etc. This traditional mechanism is very reliable. Over time, safe key locks have evolved to offer additional layers of security, such as additional levers that click in place when you lock/unlock your safe, as well as protection against lock picking. These types of locks are ideal for people who cannot be bothered with remembering a combination, or simply prefer using a key to open their safe. Mechanical combination locks are the famous safe locks you see in movies and on TV, the type where you spin the wheel every which way, hitting certain combinations along the way to release the lock. Combination locks have been the predominant lock type in safes for over a century. Today, electronic locks have broken into the market, and are making great headway security-wise. They are more convenient for everyday use than combination locks, and allow you to access the content of your safe faster. Time locks differ from the other 3 types of locks by the fact that they are installed within a safe or lockbox, in order to prevent any misuse from the outside. Banks and business use time locks extensively, to avert potential criminals taking someone hostage and forcing them to open the safe. They work in a way that a person sets the time lock to open the safe at, say, eight o'clock in the morning, when their business opens, and close at four in the afternoon, when the business closes.
Different types of locks work best for different types of safes and their intended use. Choose a safe with a type of lock that suits you and is convenient, and suits your preferred level of security and way of opening the safe.